Multi-stage thickening composition for use with packaged food items and process for using same

ABSTRACT

A multi-stage thickening composition for use in facilitating the handling and continuous packaging of a food product, and for providing a desired final shape and texture for the food product. Relatively rapid-setting and slower-setting consumable gels form one preferred thickening composition. The rapid-setting gel allows the food product to be shaped and packaged, while the slower-setting gel allows the food product to be provided with desired texture characteristics that appeal to the consumer.

BACKGROUND OF THE INVENTION

The invention generally relates to a process in which a food product tobe packaged is converted from a soft, fluid-like state to a firmer statein two or more stages. More specifically, the passage of the foodproduct through these stages is useful to provide the food product withdesired flow characteristics as it moves through the packagingequipment, and for obtaining the desired finished product body andtexture.

Food products which are fluid during processing, such as jelly, foodsauces, and dessert gels, may be difficult to process or package. Forexample, if the food product is extruded, or is required to pass overrollers, its passage through a packaging machine may be physicallyimpeded if the viscosity of the food product is too low (see, e.g., FIG.5), also causing problems with proper weight control of the packages.Conversely, the product body and texture may be physically damaged ifthe viscosity is too high, as further described below.

It is known to add a thickener, such as a consumable gel, to foodproducts. See, e.g., U.S. Pat. No. 5,567,454 to Bogdan, disclosing theuse of gelatin, fruit pectin and food starch to provide jelly with“optimal flexibility and shape-retaining qualities” (col. 6, lines12-14), and also disclosing a recessed container in which the finishedproduct shape may be formed. However, food gels have typically beenallowed to form in an undisturbed state in order to gel properly. Ifshear forces are applied to the gel as a result of packaging, the gelmay be damaged, resulting in a fractured and unacceptable finishedproduct, as has been described in U.S. Pat. No. 5,518,745 to Thota et.al as follows:

A problem with utilizing a continuous extrusion process to obtain a setextrudate is that when the product begins to set within the extruder,the possibility of degradation and physical break up of the extrudateduring conveyance increases after the transition of the mixedingredients from a liquid phase to a highly viscous solid or gel phase.The high viscosity of the setting gel increases shear forces throughoutthe extrudate as it is conveyed through the extruder. When the finalmixture of the product is shear sensitive, the extrudate tends todegrade and break apart, at least sporadically, as it is conveyedthrough. the extrusion die, significantly limiting the ability tocontinuously convey, shape, form and cut the extrudate in an efficientand continuous manner.

(Col. 2, lines 7-20).

Delaying gel formation until the product is in a packaged andfinally-formed state, however, may present problems during earlierstages of the packaging process. The product may simply be too thin orrunny to package properly as it passes through packaging machinery, suchas high-speed slice forming equipment. Thus, problems have beenencountered in packaging food products that are either relatively low orhigh in viscosity.

Some packaging equipment has been designed to move slowly enough toaccommodate gel formation. With increasing food plant size and increasedequipment automation, line speeds have increased. Packaging equipmentrequires fast through puts to justify equipment costs. The food productsmade in these plants must not only be acceptable upon shipment, but mustalso be able to tolerate these rapid line speeds. Packaging equipmenthas been specially designed to allow the passage of solid state foodproducts (see, e.g., the Thota patent, describing the use of a lowviscosity fluid continuously flowing over a channel in an extrusion dieto induce laminar flow of a gelled food product). However, it would bemore economical to provide food products designed to progress throughexisting packaging machines than to specially design machines to handlefluid food products.

In addition, packaging materials or operations may require the foodproduct itself to provide its own structural support, e.g., when aparticular shape, such as a cookie or candy, is extruded and depositedon a tray.

Various gel shapes have been described in the patent literature. See,e.g., the Bogdan patent; EPO Patent Application 99-13 0904703 to Fassinet. al., “Slice-shaped filling for sandwiches”; U.S. Pat. No. 5,417,990to Soedjak, describing multi-layered gelled products; and U.S. Pat. No.5,783,241 to Bocabeille et. al., “Method For Producing Cylindrical GelFood Products”, in which gelling is induced internally and externally ofan extruded food product using a calcium bath. However, no provision forcommercial high-speed processing and packaging of a food product using amulti-stage gel or thickener appears to be described.

Accordingly, it is an object of the present invention to provide agelling or thickening system which will introduce sufficient integrityto a food product so as to facilitate packaging of the food product.

It is another object of the invention to provide a multi-stagegelling/thickening system that provides the food product with sufficientviscosity during all relevant stages of food product formation and/orfood product packaging, while also imparting desired shape and texturecharacteristics to the food product.

It is a further object to provide a gelling/thickening system adaptablefor use with existing packaging machines, such as extruder machines forpackaging individual slices of food items, without the need to speciallyre-design such machines.

It is yet another object to provide a gelling/thickening system whichprovides a food product with desired viscosity to allow proper weightcontrol over the food product packages.

It is still another object to provide a multiple-stagegelling/thickening system which is consumable, cost-efficient andenvironmentally friendly.

DEFINITION OF CLAIM TERMS

The following terms are used in the claims of the patent as filed andare intended to have their broadest meaning consistent with therequirements of law. Where alternative meanings are possible, thebroadest meaning is intended. All words used in the claims are intendedto be used in the normal, customary usage of grammar and the Englishlanguage.

“Gel” is used here as that term is normally understood to those ofordinary skill in the art, and refers to a colloid in a form more solidthan a sol.

“Gelling agent” means a substance(s) that causes or facilitates theformation of a gel.

“Set” means for a gelled product to reach a substantially constantviscosity.

“Thickeners” mean constituents for increasing the viscosity of a foodproduct, including gelling and non-gelling agents.

“Package” means any encapsulation or covering for a food product.

“Compatible” or “Compatibility” means that two or more gels orthickening agents present in the same food product will not interferewith the: gelling or thickening process of the other(s) in a manner thatis substantially deleterious to packaging of the food product or itsconsumer appeal.

“Food Product” means any edible or consumable product.

“Jelly” means any gelled food product, including all types of jellies,jams, preserves, marmalades, fruit butters, desert gels, gelatin slices,and the like.

“Disrupt”, “disrupting”, “disruption” or “disrupted” means aninterference with the texture of the thickening or gelling agentcomposition or food matrix which occurs during or after the food producthas been initially inserted within a packaging material.

“Texture” means the physical sensation of a food product as it interactswith the human senses, including its appearance and its mouth-feel uponmastication.

“Enable” or “enabling” means to simply provide an environment for areaction or change as well as to cause that change using chemical orother means.

SUMMARY OF THE INVENTION

The objects mentioned above, as well as other objects, are solved by thepresent invention, which overcomes disadvantages of prior art thickeneror gelling systems, while providing new advantages not previouslyobtainable.

This invention has its genesis in the surprising finding that two ormore gelling or thickening agents may be added to a food product, with afirst (e.g., rapid-setting) gel or thickening agent providing thenecessary viscosity for entry and shaping of the food product incontinuous packaging equipment. The first gel or thickening agent may bedeformed and dynamically disrupted through this packaging process. Thisdisruption, as may be evidenced by an inconsistent, non-uniform, lumpyand/or granular texture formation, for example, consisting of agel-phase and a viscous liquid phase, is believed contrary to generalpractices in gelled food manufacturing, which typically require aquiescent thickener/gel setting. A second (e.g., slow-setting) gel orthickener may be used to “mask” or limit this disruption, allowing theformation of a firm, elastic, continuous food product.

In one embodiment of the present invention, a food product to becontinuously packaged by a packaging machine is to be provided with adesired texture. The food product includes a multi-stage thickeningcomposition, including preferably compatible first and second thickeningagents. The first thickening agent, which may but need not be a gellingagent, increases the viscosity of the food product so as to facilitatepackaging of the food product. In other words, as one example, the foodproduct viscosity is sufficiently increased by the first thickeningagent to avoid the problem shown in FIG. 5. The first thickening agentis then disrupted in a manner that interferes with the provision of thedesired texture of the food product. The second thickening agent permitsthe food product to be provided with the desired texture following thedisruption of the first thickening agent.

In a preferred embodiment, the food product takes the form of a slicewrapped in a plastic film. In a particularly preferred embodiment, thefood product slice is hermetically sealed within the plastic film.

As non-limiting examples, food products which may find advantageous usewith the principles of the present invention include jelly, food saucesand dessert gels.

As non-limiting examples, first or more rapid thickening or gellingagents which may be used to advantage with the present invention includepectin and Konjac gum. Also as a non-limiting example, a second orslower-setting thickening or gelling agent which may be used toadvantage with the present invention is gelatin.

In a preferred embodiment, using a vertical form and fill machine forpackaging individually wrapped food products in slices, the viscosity ofthe food product immediately prior to insertion of the food productwithin the plastic packaging film is about 5,000 centipoise or less,while the viscosity of the food product following gelling of eitherfirst or second gelling agents is about 100,000 centipoise or greater.

The present invention also includes a process for forming a food productto be packaged in a continuous packaging operation, and with a desiredshape and texture. First, a food product that includes a multi-stagethickening composition with first and second thickening agents isdispersed within other constituents of the food product. Heating of thefood product mixture may also occur at this time. The. first thickeningagent is permitted to increase the viscosity of the food product so asto facilitate shaping and packaging of the food product. The firstthickening agent is then disrupted in a manner that interferes withprovision of the desired texture of the food product. Next, the secondthickening agent is allowed to provide the food product with the desiredtexture following the disruption of the first thickening agent. Coolingof the first and second thickening agents may be provided during theirthickening or gel formation to enhance or accelerate same.

In preferred embodiment, either the first or second thickening agents,or both, constitute gelling agents.

In preferred embodiments, the increase in viscosity of the food productcaused by one or both of the thickening agents may be enhanced by adecrease in temperature.

In one embodiment, chemical additives may be added to the heated foodproduct matrix to enhance or accelerate thickening or gel formation.These chemical additives are preferably divalent cations. In aparticularly preferred embodiment, calcium chloride is used.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features which are characteristic of the invention are setforth in the appended claims. The invention itself, however, togetherwith further objects and attendant advantages thereof, will be bestunderstood by reference to the following description taken in connectionwith the accompanying drawings, in which:

FIG. 1 is a perspective view of a food product in slice form as providedby the present invention, having a smooth consistency and texture, andencapsulated within a plastic film;

FIG. 2 is view similar to FIG. 1 of a slice-shaped food product having aless desirable, inconsistent, more brittle and granular texture, as maybe caused by use of a relatively rapid-setting gel or thickener in theabsence of also using a relatively slow-setting gel or thickener;

FIG. 3 is an enlarged view of the circled portion of FIG. 2,highlighting the granular, inconsistent texture of the slice-shaped foodproduct;

FIG. 4 is a perspective view showing process steps in one preferredembodiment of the present invention;

FIG. 5 is an enlarged view of the circled portion of FIG. 4, showing thebulging problem which may occur if an attempt is made to package foodproduct which is too viscous using packaging equipment of the typedescribed here;

FIGS. 6 and 7 are side views of an open and closed blender/cooker,respectively, used in performing the process according to one preferredembodiment of the present invention;

FIG. 8 is a partial view of the blender/cooker shown in FIG. 7;

FIG. 9 is a schematic view of one preferred process according to thepresent invention;

FIGS. 10-12 are schematic diagrams showing process steps for formingexemplary food products using compositions according to preferredembodiments of the present invention; and

FIG. 13 is a graph of temperature (X-axis, in ° C.) versus centipoise(Y-axis, where centipoise is an absolute unit of viscosity inmilliPascal-seconds), with increasing units along the Y-axis indicatinga thickening or more viscous composition.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Set forth below is a description of what are currently believed to bethe preferred embodiments and/or best examples of the invention claimed.Future and present alternatives and modifications to these preferredembodiments are contemplated. Any alternatives or modifications whichmake insubstantial changes in function, in purpose, in structure or inresult are intended to be covered by the claims of this patent.

It was determined by the inventors that the need for a food product tomeet demanding rheological requirements during the packaging process mayrequire more than one stage of thickening or gel formation. Accordingly,a thickener composition was developed which includes two or moredifferent gels or thickening agents. As an example, a relativelyslow-setting gel or thickener with desirable finished productcharacteristics may be used together with a relatively rapid-setting gelor thickener which aids in packaging and assists in forming the desiredpackaged shape. Preferred gel or thickener compositions and exemplaryprocesses for using them are described below.

It was found that a complication in attempting to gel or thicken aproduct too quickly is that further deformation and/or disruption of thegel during the packaging process may damage the gel, resulting in afractured and unacceptable finished product. The surface texture of sucha product may be granular, lumpy, non-uniform and cosmeticallyunappealing in nature, and may include cracks or fissures indicating aloss of slice integrity (see, e.g., FIGS. 2-3). Also, internally, thefood matrix may be discontinuous with unacceptable texture and mouthfeel (e.g., too grainy, brittle or lumpy) and with free fluid. However,it has been discovered that the use of another, slower-setting gel orthickener may conceal or “mask” this breakage or disruption, resultingin a food product with a smoother consistency and texture (see, e.g.,FIG. 1) In other words, in the preferred embodiment the presentinvention provides a preliminary gel or thickener formation whichfacilitates continuous packaging and enables the food product to takeshape in the packaging material, as well as a second gel or thickenerformation which does not gel or thicken until after the final shape isformed and the packaging is complete. While the precise chemistry is notunderstood, it is believed that constituents of the second gel orthickener surround the granular components of the first gel or thickenerand “smooth” out their appearance, resulting in a firmer and morefinished food product texture.

A brief description of gelation and gel formation follows, as known tothose of ordinary skill in the art. This description is not intended todiscount in any way the potential for using a thickening agent asopposed to a gel in any appropriate instance.

Gelatin has proven particularly effective as a slow-setting gellingagent for use with the exemplary food products whose preparation isdiscussed in Examples 1-3, below. Gelatin is a well-known, proteinaceousgel-forming agent extracted from animal collagen tissue. The collagenmonomer is a rod-like molecule with dimensions of about 260 nm long and1.5 nm wide, and with a molecular weight of less than 300,000. Each rodis composed of three chains of molecular weight about 95,000, eachcoiled in a three-fold left-handed helix with three residues per turn.

The process of gel formation is called gelation. Gelation sufficient forthe first stage of a multi-stage gel forming process does not usuallyprovide sufficient finished product firmness. Gelatin is preferably usedin concentrations of between about 1% and 10%, depending upon thedesired firmness of the finished product.

Gelatin has the ability to form a firm gel that is alsothermoreversible. Although gelatin forms excellent gels, it is also aslow gel-forming agent. It is well established that the gel strength ofa gelatin gel increases only slowly with time. Gelatin requires arelatively low temperature (e.g., 0° C.-35° C.) for gelling, as comparedto other gelling agents. Gelatin remains soluble when heated andprovides a clear gel even at high concentrations. The gelatin used inthe current invention, described below, produces a firm gel withdesirable characteristics for controlled portions of jelly, sauces, anddessert gels. Other gelatins may prove useful with other food products.

Additional ingredients such as fruit solids, sugar, corn syrup solids,whey solids, starch, oil, colors, or flavors may be added to thegels/thickening agents described below, as needed, as long as nointerference with the multiple gel formation described below isobserved.

As to rapid-forming gels or thickening agents, polysaccharides arewidely used to gel the aqueous phase. Most polysaccharide materials,such as starches and gums, provide viscosity and thickening at elevatedtemperatures.

Thickened polysaccharide solutions depend upon the properties ofdisordered polymer chains interacting via entanglements. Rigid gelstructure is due to more specific chain interactions. This chaininteraction may be induced by a reduction in water activity, pHadjustment, ionic interactions, or by freeze thawing. Polysaccharideinteractions occur by means of the interpenetrating of flexible coils,association of rigid rods, and the formation of interchain tertiarystructures. Junction zones produce interchain tertiary structures.Examples include calcium-mediated gelation of alginates and pectins.Carrageenan gels form double helical junction zones.

The literature (see Industrial Gums, Academic Press, Inc., 1993, R LWhistler, J N BeMiller, ₃rd ed.) indicates when two chains form ajunction zone at one place along their chain lengths, other perhapsdistant reaches of each chain can collide and form a junction zone withother molecules. This process of random junction zone formation betweendifferent molecules can continue until many, if not most, of thepolysaccharide molecules become involved in a great three-dimensionalnetwork that may fill the entire vessel. The gel will possess a strengthdependent on the strength of intermolecular bonding at the junctionzones. If the bonding is weak, it may be broken and the total gelstructure disrupted by stirring. In this case the weak gel is said to bethixotropic. The forces of stirring supplies sufficient energy to breakmany, or even most, of the junction zones and the viscosity of thedispersion decreases. When stirring is stopped, the molecules may againcollide in normal translation, or Brownian-like motion, and junctionzones re-establish to some degree.

This same literature indicates that when the junction zones are ofgreater strength, a more identifiable gel forms that may not be easilybroken by stirring and may be strong enough that, under force, the gelwill separate or cleave as seen with gelatin gels. Such a gel may bereliquified if the junction zone energies are low enough that simpleheating may energize the molecules sufficiently to cause them to tearapart from each other. Once formed, a gel may undergo lengthening of itsjunction zones by the molecules sliding over each other or by simplymoving together at the junction zone ends so as to increase the lengthof the zone. This will cause a tightening of the overall networkstructure and a decrease in the water-filled spaces between themolecules. Hence, water is exuded from the gel to produce syneresis, asis commonly observed.

This discussion suggests that a weak gel can form, be broken, and reformto some degree, but that a firmer gel may not reform without reheatingor forming some additional type of gel.

Cation-mediated polysaccharides, such as alginates, low methoxyl pectinand carrageenans, are able to produce rapid-setting gels at hightemperatures. Rapid-forming gelling agents have the characteristic offorming gels at high temperatures, preferably above 65° C.

Some of the types of rapid gel forming agents that may find advantageoususe with the present invention include konjac, carrageenan, and lowmethoxyl pectin. Konjac is the generic name for the flour formed fromgrinding the tuber of the Amorphophallus konjac plant. It is classifiedas a glucomannan. Its average molecular weight is between 200,000 and2,000,000, which accounts for its high pseudoplastic viscosity. Konjacis synergistic with kappa carrageenan, xanthan, and locust bean gum toform thermally reversible gels. Konjac is a non-ionic polysaccharide andits gel structure is not affected by calcium, potassium, or sodium.

Pectin is a structural polysaccharide found in all higher plants. Allpectin contains segments of galactopyranosyluronic acid units with someof the carboxyl groups esterified with methanol. If pectin is treatedwith ammonia, some of the methyl carboxylate groups are converted incarboxamide groups, resulting in an amidated pectin. Pectins with adegree of esterification (DE) greater than 50 are called high esterpectins or high methoxyl (HM) pectins, while those with DE less than 50are called low ester pectins or low methoxyl (LM) pectins. HM pectinsrequire high concentrations of soluble solids and a low pH to gel. LMpectins require only the presence of divalent cations. A rapid gel orthickener formation can be observed when dissolved LM pectin is combinedwith a divalent cation such as calcium.

Carrageenan may also be used as a rapid-setting gel or thickener. Use ofcarrageenan from seaweeds (i.e., Irish moss) for food thickeners datesback hundreds of years. Carrageenan is a group of sulfated galactansextracted from red seaweeds. There are three major fractions ofcarrageenans: kappa, iota, and lambda. The fractions contain the samealternating unit backbone but vary in the extent and position ofsulfation. Kappa and iota carrageenan have the ability to formthermoreversible gels upon cooling of hot aqueous solutions containingvarious salts. Kappa carrageenan gels most strongly with potassium ions.Iota carrageenan gels most strongly with calcium ions, and lambda doesnot form gels.

According to the present invention, the amount of rapid gel-forming orthickening agents used depends upon the required firmness for theparticular food product being extruded into the packaging material. Itis desirable to have sufficient material present to allow filling atabove 65° C., although lower temperatures are acceptable. An additionalrestraint is that the formation of the first (rapid-setting) gel orthickener should not be so close to the second gel or thickenerformation that the second gel or thickener formation is disrupted.Levels of between 0.2% and 2% for the first setting gel or thickenerwere found acceptable. (Unless otherwise stated, all percentages givenhere are weight percentages.) Addition of a cationic source such ascalcium or potassium may be required to achieve an appropriate initialset. In this case, sufficient dispersion is recommended for an even gelor thickener to form.

Starch is the major reserve polysaccharide of higher plants, where itoccurs mainly in storage organs such as seeds, tubers, or roots. Itexists as water insoluble spherical granules. The granules can befractionated into two major components called amylose and amylopectin.Amylose is a linear polymer of a(1->4) linked D-glucose. Amylopectincontains chains of a(1->4) linked D-glucose but is a multiple branchedstructure with branches linked at position 6. Solutions of starchgranules swell with heating, undergoing a process called“gelatinization” at sufficiently high temperatures. Swelling leads tosolubilization of amylose. Heating results in porous amylopectingranules suspended in hot amylose solution with little solubilization ofthe amylopectin occurring. Upon cooling, amylose forms turbidviscoelastic pastes or, at higher concentrations, opaque elasticthermo-irreversible gels.

In addition to thickening and gel formation, polysaccharides interactwith each other to various degrees. Locust bean gum reacts withcellulose to result in gel formation. Locust bean gum reacts with agar,and agar with carrageenan to increase gel strength. Xanthan and tara gumreact with locust bean gum to increase gel strength. Konjac flour reactswith xanthan to gel at a higher temperature than konjac alone. At times,interactions are unfavorable for thickening and gel formation, causing areduction in these properties.

For the present invention, which involves multiple gelling or thickeningevents or stages, the thickening/gelling agents should be compatible. Inother words, the gel or thickening formation of one preferably does notdetract from the gel formation of the other. As one example, gelatin maynot gel properly with substances that block interaction of helices.Also, to provide different gel stages, thickening agents which do notgel simultaneously should be selected, such as those whose gel orthickening formation is separated by temperature and/or time.

Three examples will now be described in which two-stage gel/thickeningcompositions were used to increase the viscosity of naturally fluidic orrunny food products.

EXAMPLE 1

Using the present invention, an individually wrapped jelly slice wasmade according to the following formula (numbers in percentages, byweight), as further shown in FIG. 10:

Grape juice concentrate 27 Frozen retail commercial brand Pectin(Unipectin AMP 285) 1.5 SKW, Atlanta, Georgia 30340 250 bloom gelatin 3Germantown Mfg. Inc. Westchester, PA 19380 Sugar (table sugar) 40 CriscoVegetable oil 1.4 Citric acid (50% solution) 0.4 ADM Shawnee Mission,Kansas 66207 Calcium chloride solution (45%) 0.5 Rhodia Labs, Madison,WI Water/steam 26.2

The pectin and gelatin was dry blended by hand with 5 times their weightof sugar. The dry blend was then added slowly to the juice and waterwhile agitating in a 200-pound capacity Rietz-style twin screwhorizontal auger cooker (available from Green Bay Machinery, Green Bay,WI), as shown in FIG. 4. The amount of water used was reduced by theanticipated amount of steam to be added during heating and an amount todilute the calcium chloride at a 1:10 ratio. Typical steam values arefrom 5-10% of the finished product weight dependent on finished cooktemperature. Vegetable oil was added to reduce foam formation. Theremainder of the sugar was added and the mixture was heated with directsteam (FIG. 6) to a temperature of 90° C. and held for 2 minutes. Theheating from the cold tap water temperature to final cook temperaturewas about 12-20° C. per minute. Heating was also accomplished withagitation by the twin screw auger rotating at about 60-180 rpm. Afterthe final cook temperature and an additional hold at that temperature of2 minutes during fast agitation, the auger speed was reduced to about20-40 rpm. The citric acid solution was then slowly added at about 4mls. per second. Next, the calcium chloride solution is added at about 1ml. per second. Calcium chloride solution was added very slowly to avoidlocalized gel formation. The blend is allowed to decrease in temperatureto about 74° C. until the gelation causes thickening sufficient toextrude into the packaging equipment, as shown in FIGS. 7-8. As may beseen in FIGS. 7-8, while gelling/thickening has occurred, the texture ofthe food product is somewhat lumpy, granular and non-uniform, and is notdesirable as a finished, consumer-ready product, due to the dynamicmixing process. The cooling process takes about 5-15 minutes with slowspeed agitation as described above.

The jelly food product may be gravity-fed from the blender/cooker into aholding tank and then, using a positive displacement pump, may betransported into a fill tube for entry into the packaging material.Following entry of the jelly into the packaging film, the film wasformed into a flat ribbon and cooled in a cold water trough of about 6°C. The ribbons were then further shaped and further flattened, crimpedinto slice portions, and the crimped areas were cut to form individuallywrapped slices. The slices were stacked and allowed to cool underrefrigeration temperatures until the desired finished product firmnesswas obtained. The packaging operations recited in this paragraph may beperformed by a slice-shaping and packaging machine as described in U.S.Pat. No. 5,440,860 to Meli, et. al. whose disclosure is incorporatedherein by reference, and as generally shown in FIGS. 4 and 9.

Slice-forming and wrapping machines described in the '860 patent providerapid packaging of food product slices within a flexible plastic film,at speeds, e.g., over about 1000 slices/minute.

It will be understood that disruption of the rapid-setting pectin gel bythis packaging machinery will occur, otherwise causing the jelly to loseits smooth texture and appropriate consistency. However, theslow-setting gelatin will provide a finished, appropriately texturedjelly slice, as shown in FIG. 1, which is firm enough to maintain itsintegrity in a slice form while either consuming the product directly orusing it in some other application such as with a sandwich.

It is noted that attempts to package jelly slices using the Melipackaging machinery in the absence of a rapid-setting gel have provenunsuccessful, as the runny jelly ribbon catches and bulges, and refusesto wind around the rollers, as shown in FIG. 5. Increased viscosityneeds to be imparted to the food product to provide weight control andpermit flattening of the food product within the packaging film.

EXAMPLE 2

An individually wrapped slice of barbeque sauce with good meltingproperties was made according to the present invention, using thisformula, as further shown in FIG. 11:

Prepared barbeque sauce 90.5 Commercially available 250 bloom gelatin 6Germantown Mfg., Inc. Westchester, Pa 19380 Konjac flour 1.5 FMC Corp.,Philadelphia, (Nutrical ® Konjac powder) PA Sugar (table sugar) 2

One-half of the barbeque sauce was added to a 200-pound capacityRietz-style twin screw horizontal auger cooker (Green Bay Machinery,Green Bay, Wis.). The dry ingredients were blended together and mixedinto the remainder of the barbeque sauce using a wire whip on a Hobartmixer (Blakeslee B-20, G S Blakeslee & Co., Chicago, Ill.). The sauceand gum preparation from the Hobart mixer was then combined with thesauce in the cooker. The temperature was increased using a steam jacketat a rate of increase of about 2-5° C. per minute to 76° C. using mediumagitation at about 60-180 rpm. After this cook temperature was reached,the mixture was cooled to about 76° C. using slow agitation at about2040 rpm until sufficient gelation occured to allow packaging. Thecooling process takes about 5-15 minutes with slow agitation asdescribed above. The material was then transferred to the extruder andpackaging machine described in the '860 patent, and extruded into thepackaging film. The film with the food product inside was thenflattened, forming a continuous ribbon of sauce. The ribbon was cooledin a cold water trough of about 6° C. The ribbon was crimped intoportions and the portions cut into individually wrapped slices. Theslices were stacked and allowed to cool until acceptable firmness andgood film separation were achieved.

Finished slices were firm enough to handle and would melt sufficientlyto enrobe the material to which they were applied, without flowing offof the material. Using a barbeque sauce dry mix in place of the liquidpreparation worked equally well and allowed the use of direct steamheating.

EXAMPLE 3

An individually wrapped dessert gel with sufficient integrity anddryness for handling was made according to the present invention, usingthis formula, as further shown in FIG. 12:

250 bloom gelatin 4.0 Germantown Mfg., Inc., Westchester, PA 1 9380Pectin (Unipectin) 1.5 SKW, Atlanta, GA 30340 AMP 285) Table sugar 30Tri-calcium citrate 0.2 GBI, Rolling Meadows, IL 60008 Citric acid (50%solution) 0.3 ADM, Shawnee Mission, KS 66207 Color (FD&C Red #40) 0.005Hilton Davis, Cincinnati, OH 45237 Flavor (N&A Strawberry 0.5 T.Hasegawa USA, Inc. FC9120) Cerritos; CA 90703 Water/steam 55.7

The gelatin, pectin, sugar, calcium citrate, flavor and color were dryblended by hand in a plastic bag and added slowly to the cold water in a200-pound Rietz-style twin screw horizontal auger cooker (Green BayMachinery, Green Bay, Wis.). The agitation is set high (about 60-180rpm) to avoid lumping. The water was reduced by the anticipated amountof steam to be added and by one pound of water needed to slurry thecalcium citrate. Typical steam values are from 5-10% of the finishedproduct weight, dependent upon finished cook temperature. The mixturewas cooked with high agitation to 90° C. at a rate of increase of 12-20°C. per minute and held for 2 minutes with continued high agitation.Next, the citric acid solution was added, followed by color and flavor.The mixture was then cooled to about 66° C. until sufficient gelformation was developed to facilitate packaging. This cooling processtakes about 5-15 minutes, at slow speed agitation (about 20-40 rpm). Thematerial was then transferred to the packaging device described aboveand extruded into the packaging film. The film was then flattened,forming a continuous ribbon of dessert gel. The ribbon was then cooledin a cold water trough of about 6° C. The ribbon was crimped intoportions and the portions cut into individually wrapped slices. Theslices were stacked and allowed to cool until acceptable firmness andgood film separation were achieved.

Referring to FIG. 13, there is shown a graph of temperature (° C.)versus viscosity (in centipoise, or milliPascal-seconds). The diamondsrepresent a food product with a multi-stage gelling compositionaccording to the present invention (see the formula recited in Exhibit1, for forming jelly slices). The triangles represent that food product,but without the use of calcium chloride. The circles represent that foodproduct, but without the use of gelatin. As may be seen, the lack ofcalcium chloride delays thickening, while the lack of gelatin impedesgel formation. As may also be seen, there is an order of magnitudeincrease in viscosity when the first gel forms. There is also anapproximate order of magnitude increase in mixture viscosity as thesecond gel is forming. As an example, food products according to thepresent invention have an apparent viscosity (according to theviscotester, Model No. VT550, Haake, USA, Paramus, N.J., used to makethe measurements shown in FIG. 13) of about 1000 centipoise duringfilling of the food product within the packaging material. On the otherhand, the apparent viscosity of the food product during gel formation isabout 10⁵ or greater.

Suitable thickening and gel forming agents that may find advantageoususe with the present invention include at least: gelatin, xanthan,curdlan, agar, alginates, carrageenans, guar, locust bean, tara,methocel, fenugreek, pectin, gellan, other derivatives of cellulose, andstarch.

Suitable temperatures at which the food product is provided to theextruder for insertion into the packaging film (“fill temperature”) andat which the food product exits from the cooling bath (“exittemperatures”) will generally be known to those of ordinary skill in theart, and vary depending upon the packaging machine used, the processingspeed, the film and, of course, the food product and its desired shapeand texture. As examples, with regard to the jelly slice formedaccording to Example 1, above, suitable fill temperatures were found tobe in the range of about 70-75° C. and suitable exit temperatures werefound to be in the range of about 5-10° C. As further examples, withregard to the barbecue sauce and dessert gel slices of Examples 2 and 3,suitable fill temperatures were found to be in the range of about 70-75°C. and about 65-70° C., respectively, while suitable exit temperatureare the same as for Example 1.

Chemical additives, such as calcium chloride or other divalent agentssuch as other chloride or calcium acidified solutions, may be added tothe gels or thickening agents described above for the purpose ofaccelerating the rate of gelling/thickening, and to bring aboutgelling/thickening in a more measured and controlled manner.

It will be understood that the present invention may find advantageoususe with various types of continuous packaging machines that shapeand/or extrude food products, including food products that are shapedinto slice, loaf and other forms. In one particularly preferred form,the slices may be hermetically sealed as taught in the '860 patentincorporated here by reference.

It will also be understood that in its broadest aspects, the presentinvention is not limited to the use of “gels” or the gelling phenomenon.Instead, any multi-stage thickening agents may be advantageouslyemployed by the present invention, with the different stages beingtriggered by (e.g.) time or temperature variations or combinations ofsame, by additive chemical agents, or by other means. Also, combinationsof gelling and thickening agents may be employed (e.g., a rapid-settingthickening agent may be combined with a slow-setting gel, or arapid-setting gelling agent may be combined with a slow-settingthickening agent).

The present invention also provides enhanced weight control over theresulting food product packages. Thus, since the first gel/thickenerallows more even filling of the package, little or no variance in weightbetween packages may be obtained.

The above description is not intended to limit the meaning of the wordsused in the following claims that define the invention. Rather, it iscontemplated that future modifications in structure, function or resultwill exist that are not substantial changes and that all suchinsubstantial changes in what is claimed are intended to be covered bythe claims.

We claim:
 1. A food product comprising a food sauce or jelly to becontinuously packaged within a flexible wrapping material and providedwith a desired texture and consistency through sequential thickenerformation, disruption and reformation, comprising: a multi-stagethickening composition comprising compatible first and second thickeningagents which thicken at different times during the packaging process;the first thickening agent comprising a plant-based or microbial-basedgelling agent initially substantially increasing the viscosity of thefood product to facilitate packaging of the food product, the firstthickening agent being disrupted by the packaging process after the foodproduct has been initially inserted within the flexible wrappingmaterial, the disruption interfering with the desired texture andconsistency of the food product, and the second thickening agentcomprising a gelatin and causing the food product to again substantiallyincrease in viscosity following the disruption of the first thickeningagent, the second thickening agent masking the disruption of the firstthickening agent caused by the packing process to thereby provide thefood product with the desired texture and consistency.
 2. The foodproduct of claim 1, wherein the food product comprises a slice and thepackage comprises a plastic film enclosing the slice.
 3. The foodproduct of claim 2, wherein the food product slice is hermeticallysealed within the plastic film.
 4. The food product of claim 1, whereinthe food product comprises jelly.
 5. The food product of claim 1,wherein the food product comprises a food sauce.
 6. The food product ofclaim 1, wherein the first thickening agent comprises low methoxylpectin.
 7. The food product of claim 1, wherein the first thickeningagent comprises Konjac gum.
 8. A food product comprising a food sauce orjelly to be continuously packaged within a flexible wrapping materialand provided with a desired texture and consistency through sequentialgel formation, disruption and reformation, comprising: a multi-stage gelcomposition comprising compatible first and second gelling agents whichthicken at different times during the packaging process; the firstgelling agent comprising a polysaccharide and initially substantiallyincreasing the viscosity of the food product to facilitate packaging ofthe food product, the first gelling agent being disrupted by thepackaging process after the food product has been initially insertedwithin the flexible wrapping material, the disruption interfering withthe desired texture and consistency of the food product; and the secondgelling agent causing the food product to again substantially increasein viscosity following the disruption of the first gelling agent, thesecond gelling agent masking the disruption of the first gelling agentcaused by the packing process to thereby provide the food product withthe desired texture and consistency; wherein the viscosity of the foodproduct immediately prior to packaging is about 5,000 centipoise orless, and the viscosity of the food product following gelling of eitherthe first or second gelling agents is about 100,000 centipoise orgreater.
 9. The food product of claim 8, wherein the food product is afruit jelly.
 10. A process for forming a continuously packaged foodproduct comprising a food sauce or jelly to be provided with a desiredtexture using sequential gel formation, disruption and reformation,comprising the steps of: dispersing a multi-stage gel comprisingcompatible first and second gelling agents which thicken at differenttimes during the packaging process within other constituents of the foodsauce or jelly, the first gelling agent comprising a polysaccharide andincreasing the viscosity of the food sauce or jelly so as to facilitateits shaping and packaging; the packaging process disrupting the firstgelling agent in a manner that interferes with the desired texture ofthe food sauce or jelly; and the second jelling agent masking thedisruption of the first gelling agent caused by the packing process andgelling to provide the food sauce or jelly with the desired texture. 11.The process of claim 10, wherein the increase in viscosity of the foodproduct caused by one or both of the gelling agents is enhanced by adecrease in temperature.
 12. The process of claim 10, further comprisingthe step of heating the gelling agents during their dispersion withinthe other constituents of the food product.
 13. The process of claim 10,further comprising the step of adding a chemical to the gelling agentsduring their dispersion within the other constituents of the foodproduct to accelerate the increase in viscosity of the food product. 14.The process of claim 13, wherein the chemical comprises a divalentcation.
 15. The process of claim 14, wherein the divalent cationcomprises calcium.
 16. The process of claim 12, further comprising thestep of cooling the heated mixture to a temperature sufficient toenhance the ability of the first gelling agent to increase the viscosityof the food product and facilitate its shaping and packaging.
 17. Theprocess of claim 12, further comprising the step of cooling the foodproduct following its packaging to a temperature sufficient to enhancethe ability of the second gelling agent to provide the food product withthe desired texture.
 18. The process of claim 10, wherein the foodproduct is extruded into slices by the packaging operation.
 19. Theprocess of claim 18, wherein the food product slices are eachhermetically sealed.
 20. The process of claim 10, wherein the foodproduct is extruded into slices by the packaging operation and is sealedwithin a flexible plastic film at speeds in excess of about 1000slices/minute.
 21. The process of claim 10, further comprising the stepsof: heating the food product during the dispersion step to facilitatemixing of the gelling agents within the food product; cooling the foodproduct to a fill temperature at which the food product is insertedwithin the flexible wrap, to thereby substantially increase theviscosity of the first gelling agent and, thus, the food product, tofacilitate its shaping and packaging; and further refrigeration of thefood product to an exit temperature at which the food product exits fromthe packaging process.
 22. The process of claim 21, further comprising aconsumption step in which the unpackaged food product is permitted tomelt sufficiently to enrobe a material to which it is applied.
 23. Theprocess of claim 21, wherein the fill temperature comprises betweenabout 65°-75° C.
 24. The process of claim 21, wherein the exittemperature comprises between about 5°-10° C.
 25. The process of claim22, wherein during the consumption step the viscosity of the foodproduct is substantially the same as the viscosity of the first gellingagent.